Origin

Late Middle English: from medieval Latingestura, from Latingerere 'bear, wield, perform'. The original sense was 'bearing, deportment', hence 'the use of posture and bodily movements for effect in oratory'.

In the Middle Ages a jest was not a joke but a notable exploit. It was spelled gest, and came from the Latin word gesta ‘actions, exploits’. It has the same root as gesture (Late Middle English). Jest came to be used for a narrative of someone's deeds, and from that became a word for ‘an idle story’ and then ‘a joke’.